The invention relates to a conductive network having an improved interconnection between conductive traces of two conductive devices, and a method of connecting such devices together.
Conductive devices such as printed circuit boards (PCB""s) are used widely in the computer and electronics industries to transfer electric signals throughout an apparatus or from one apparatus to another apparatus. Each PCB includes a plurality of conductive or signal traces disposed on a substrate, and each trace has a contact portion that mates with a contact portion of another PCB so as to electrically join the PCB""s together.
A prior method of interconnecting such contact portions includes providing a pin and socket connection between two PCB""s. With such an arrangement, the contact portions of one PCB slide across the contact portions of another PCB when the pins associated with one PCB are mated with the sockets associated with the other PCB. This sliding movement is referred to as wiping, and provides a means to break through oxides on the contact portions. Such wiping also serves to displace insulating debris that may have collected on the contact portions.
With flexible circuitry, however, surfaces are usually joined vertically such that wiping does not occur. As a result, other methods for breaking through oxides are usually employed. For example, surface imperfections may be provided on the contact portions of one PCB that plastically deform contact portions of another PCB. Such surface imperfections may include a gold bump or a plurality of particles positioned on each contact portion. These methods, however, are time consuming and costly to implement.
The invention addresses the shortcomings of the prior art by providing an improved method of connecting conductive devices together, as well as a conductive network having an improved interconnection between conductive devices.
Under the invention, a method of connecting a first conductive device to a second conductive device is provided. The first conductive device has a first conductive trace supported by a first substrate. The first trace has a generally planar first surface spaced away from the first substrate that defines a first edge. The second conductive device has a second conductive trace supported by a second substrate. The second trace has a generally planar second surface spaced away from the second substrate that defines a second edge. The method includes joining the first edge of the first trace with the second trace to form an area of contact such that a portion of the first surface proximate the area of contact is non-parallel with a portion of the second surface proximate the area of contact.
The area of contact formed between the traces may be any suitable area of contact, such as a line of contact or a point contact. For example, the joining step may comprise joining the first edge of the first trace with the second surface of the second trace to form a line of contact. As another example, the joining step may comprise joining the first edge of the first trace with the second edge of the second trace to form a point contact.
The method may further include removing sufficient substrate material from the first substrate to sufficiently lessen stiffness of the first trace. The joining step may then include forcing the first edge of the first trace together with the second edge of the second trace such that the first trace twists with respect to the second trace.
Further under the invention, a method of connecting a first conductive device to a second conductive device is provided. The first conductive device has a first conductive trace supported by a first substrate. The first trace has a first surface spaced away from the first substrate that defines a first edge. The second conductive device has a second conductive trace supported by a second substrate. The second trace has a second surface spaced away from the second substrate that defines a second edge. The method includes establishing two angles between the first and second edges; and joining the first edge with the second trace to define an area of contact.
A conductive network according to the invention includes a first conductive device having a first substrate and a first conductive trace supported by the first substrate. The first trace has a generally planar first surface spaced away from the first substrate, and the first surface defines a first edge. The network further includes a second conductive device having a second substrate and a second conductive trace supported by the second substrate. The second trace has a generally planar second surface spaced away from the second substrate. The first edge is in contact with the second trace so as to form an area of contact, such that a portion of the first surface proximate the area of contact is non-parallel with a portion of the second surface proximate the area of contact.
More specifically, a conductive network according to the invention includes a first printed circuit board having a first substrate and a plurality of first conductive traces supported by the first substrate. Each first trace has a generally planar first surface spaced away from the first substrate, and each first surface defines a slanted edge. A second printed circuit board is in electrical communication with the first board. The second board has a second substrate and a plurality of second conductive traces supported by the second substrate. Each second trace has a generally planar second surface spaced away from the second substrate, and each second surface defines a side edge. The network further includes a connector assembly including first and second connector portions that are engageable with each other. The first connector portion is connected to the first board, and the second connector portion is connected to the second board. When the connector portions are engaged with each other, the first traces are offset with respect to the second traces, and each slanted edge of the first board is in contact with a side edge of the second board so as to form a point contact, such that a portion of each first surface proximate a respective point contact is non-parallel with a portion of a respective second surface proximate the respective point contact.
Theses and other objects, features and advantages of the invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in conjunction with the accompanying drawings.